Running a smartphone platform is a group effort. You’ve got software engineers, designers, support staff, marketing teams, and so many more other roles each contributing in their own way. At the upper echelons, management’s calling the shots, and the higher we go, the further we move away from little details and start getting into more big-picture stuff: where’s the platform going, and how do we get it where it needs to be in the next five years? At Microsoft, with Windows Phone, that means execs like Terry Myerson, but go high enough and you get to CEO Steve Ballmer. Ballmer’s been at that post since early 2000, through all the Pocket PC, Windows Mobile, and now Windows Phone days. Going forward, however, Microsoft’s going to have to find a new voice to lead it, announcing today that Ballmer intends to retire within the next year.

There’s no exit date set in stone just yet, but Ballmer plans to wrap things up as CEO within the next twelve months. In the meantime, Microsoft’s board will start evaluating candidates for Ballmer’s successor, setting up a special committee for the purpose. As should be only fitting, Bill Gates will be a member of that team tasked with finding the next CEO.

We don’t expect this shake-up to have any immediate effect on Windows Phone – surely, there are plenty of other people much more directly affiliated with the platform who are sticking around – but it will be interesting to see how Ballmer’s replacement ends up viewing Windows Phone as part of the larger Windows ecosystem, and what resources he or she makes available to aid the platform’s continued growth.